Medical practitioners currently use Percutaneous Endoscopic Gastrostomy (PEG) and Percutaneous Endoscopic Jejunostomy (PEJ) techniques to place catheters or tubes within the gastro-intestinal tract. Three main PEG techniques are used to place gastro-intestinal tubes: Sacks-Vine, Ponsky, and Russell. These techniques are well-known in the art.
Gastrostomy tubes, which are a type of gastro-intestinal tubes, often have an anchoring device, or internal bolster, on their distal ends. These bolsters are formed with a lateral extent which is wider than the penetration diameter to prevent premature removal of the tube from the penetration. The bolsters often have a dome, mushroom, or Malecot structure.
Due to the lateral extent with which the internal bolsters are formed, percutaneous placement of tubes having such bolsters through a penetration is difficult, and current techniques do not adequately provide for placement of such tubes. When placing a gastrostomy tube with internal bolster at its distal using either Sacks-Vine or Ponsky technique, for example, the tube and bolster are dragged through the esophagus and into the stomach. When performing percutaneous placement according to the Russell technique, practitioners typically use catheters with a balloon on the distal end which can be inflated once the tube is placed within the stomach, instead of using a tube having a bolster with lateral extent as described above.
Typically, the initial penetration is maintained such that a stoma, or fistulous tract, is allowed to form, which connects the stomach wall to the external abdominal wall. In the prior art, the initially-placed gastrostomy tubes are replaced using the same techniques used as to place the initial tube; i.e. according to either the Sacks-Vine, Ponsky, or Russell technique. Alternatively, they are placed by insertion through the stoma.
Various devices have been used for inserting a gastro-intestinal tube having an internal bolster through a stoma. Use of these devices typically involves obturating or realigning the internal bolster, or axially elongating the internal bolster prior to insertion. See e.g., U.S. Pat. Nos. 5,248,302, 5,007,900, and 5,454,790.
Several deficiencies exist in the prior art techniques. For example, Russell technique is a complicated placement method which is not conducive to placing gastrostomy tubes having internal bolsters. In addition, those techniques which use obturation for placing tubes by insertion through a stoma often require specialized bolsters capable of engaging an obturator rod, and access tubes equipped with such specialized bolsters are typically expensive. See e.g, U.S. Pat. No. 5,248,302. Furthermore, prior art techniques which involve axial elongation and radial compression of the access tube require a grade of access tube which can sustain such axial tension and radial compression. See e.g. U.S. Pat. No. 5,454,790. Those techniques may also require a sheath capable of compressing the tube to a diameter smaller than the diameter when under axial tension or radial compression. Further still, techniques used with access tubes having T-bar bolsters in which the T-bar bolster is aligned with the tube shaft, such as that described in U.S. Pat. No. 5,007,900, often do not sufficiently reduce the lateral extent of the tube's distal end to a size that can be easily inserted into the stoma.